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F.. C. YHSGH: n THE PROCESS 0I' PHOTOMBGIIANIGAI. PRINTING IN COLORS. ,180... 287,938. Patented Nov; 6,1883.

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I'. 0.1116503 TEE PROCESS OP PHOTOMBGHANIGAL PRINTING IN COLORS.

No. 287.938. .Y Patented NOV. 6, 1883,.

8 Sheets-Sheet 8.

Patented Nov. 6, 1883.

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(Specimens.)

THE PRGIISS OI PHOTOMECHANIGAL PRINTING IN COLORS.

U NITgED STATES 4lnfrnr OFFICE.

. FRIEDRICH cnnnrlscn, or NUREMB'ERG, BAVARIA, GERMANY.

PRoeEssoF PHOTO-MECHANICAL PRINTING IN coLoRe.

. SPECIFICATION forming part of Letters Patent No. 287,938, dated November 6, 1883.

Application filed October 20,1881. (Specimens.) Patented Vin Germany June 5, 1881, No. 17,410; in England August 12, 1881, No. 3,504; in Austriadlungary October 6, 1881, No. 33,363 in France October 2t?, 1881, No. 145,472, and in Belgium October 29, 1881,

To LEZ whom t may concern.-

Be it known that I, FRIEDRICH Cani. Hscn, v

of Nuremberg, Kingdom of Bavaria, Germany, have invented an Improvement in thel-rocess of Photo Mechanical Frint-ing in Colors by Means of a Color-Scale, of which the following is a specification.

The nature ofm'y invention relates to new 'and useful improvements in that class of photographic-printing processes which are knownall its shades and tints, may be mechanically defined, for the purpose of reproducing it by light printing or any like process of super` imposing colors, all as fully hereinafter described and set forth. From a given negative of the desired object are printed, by the wellnown process of photo-mechanical printing, as manyprints as may be required, their number being determined bythe number of colors to be combined, one print being required lfor the production of a monochrome lfor each color. -According to the current theory of colors, each color-tolle is to be regarded as composed of given percentages of the three primary colors-yellow, red, and blue-and according to this theory all colors in nature could be perfectly reproduced in printing by,

the use ofany or all oi' these three colois. The nat-ure of our coloring materials, however, presents an unsurmountable obstacle to carrying this theory into practice, as none of our coloringmaterials possess the depth, brilliancy, and transparency combined which we see in the prismatic colors in nature; therefore forced, in order to imitate all and every natural color in print, to enlarge upon our means for producing it. For this purpose I devised a color-scale containing practically all the colors, in various shades and tints, asv they are found in nature or in paintings, and wherein each color has been produced and can We are j be reproduced in a mechanically well-defined manner by means of photo-mechanical printing in colors. The practical use of such a color-scale is self-evident when it is considered that the photographic negati-ves of colored objects very often do not furnish true lights and' shades of the colors, that in the process of light `printing the superimposed colors, owing to lack of transparency, more or less destroy the effect of the underlying colors, and that the transfer ofthe colors from the plate to the 'print is different in degree, according to the color coming on printed or unprinted spots.

tofore light printing in colors totally uncertain Vin its final results, are all anticipated in the use of my color-scale, which gives a mechanically well-deiined way for obtaining a desired result.

The principle upon which my color-scale is constructed will be clearly understood from the following practicalexample, reference being had to the drawings, of which- Figures l to 11", inclusive, Vshow a scale in black and different tones of gray in a variety 'of geometrical combinations 3 Fig. 2A, a portion of the lcolor-scale printed therefrom. Figs.. 1 and 2 are diagrams.

In the drawings, in Figs. lA to 1F,in clusive, are shown a number of black and gray squares, halfsquares, and other geometrical figures arranged in various combinations, from jet black to light gray, in iive well-defined degrees of shade.

The absolute blackiwe will characterize by f2,

while the different gradations of gray may be represented by the fractions e i the latter representing the lightest shade of gray. These shades arey in practice produced.' with the brush, although they are on the drawings shown in lines, (to allow of their being photolithographed) From this scale (in black and gray) a photographic negative is obtained and' a light-printing plate produced, from `which plate six impressions are to be printed in the 'following six colors: lirst, a yellow color, a,- second, a red color, b; third, a blue color, c; fourth, a neutral tint, (modulation t0ne,) d; nfth, a local or flesh tint, e; sixth, a second red color, f. The printing is done in the following manner: After the iirst color is print- -All` these influences, which have made here- ICO ` to the right, and so each successive color is printedv upon the preceding one by shifting the plate the width of one square to the right. Thus, for instance, the square M in Fig. 1A will register in the second impression with the vsquare N in the third with the square O, in the fourth with the square l?, in the fifth with the square Q, and in the sixth and last impression with the square R. Now, if we characterize 4the six colors above named in their given order with the letters a b c d e f,the color upon the square M, after the six impressions have been made, will be composed, first, of g .yel-

low; secondly, no red, (the square N being a blank one, ,and therefore takes up no color on the plate) thirdly, of blue; fourthly, of of neutral tint; 'iifthly, cfg of esh tint 5 sixthly, of of red, superimposed in the order herein named. h' -A In Fig. 2Ai'isI shown the composition of the colors thus obtained from Fig. l, beginning with the line H,'the printed squares to the left of 'this line being omitted, as they wouldl be unnecessary repetitions of colors mostly obtained at the end of the scale. When obtained in practiee, `the color-scale thus produced by the'six successive impressions in the manner describedfwill show one thousand six hundred and twentyI colored fields, (this being the number of squares on Fig. 1F,) which Vcontain'a' great"va'riety of colors differing (with few exceptions) .from each other, or

where alike are ,ften'produced in a very dif-l ferent manner, as their exact definition in figures will show. Eacheld of this large collection of colors and tones displayed upon this color-scale is new4 numbered and marked in j. figures (as shown in.`Fig.-2^, whereon the colf-ors are, however, omitted. denoting the com- 'position ofthe colors.' VThus No. 1,which is produced-by printing upon the vffeld T first yellow, then red from eld U, blue from field V,

neutral from field NV, flesh tint from field X,

and red from field Y, in the order described, is

marked iga, -15- b, (meaning the half square,)`% 0, -gd, e, (for each respective half-square.)

With the help of this color-scale thus perfected it is a very easy matter for the artist by l' comparison with any color of an original to find out how many color-plates will be needed for the production of suchcolor, and, further, what percentage of each color has to be taken, the'same succession of colors as given ony the .scale to be followed in the printing.

The manner of obtaining color-scales after f the above-explained principle can be greatly .varied as the succession and number of the foundation-colors may be changed'. The colorscales may also advantageously be arranged according to color-tones, whereby the looking up of colors is greatly facilitated.

The process of colored light printing by the use of the above-described color-scale is conducted as follows: As mentioned in the beginning, a number of light prints in neutral gray are obtained from the given negative,

and serve as foundation for the production of monochrome-plates. First,acomparison ofthe original with my color-scale will easily decide how many and what plates are necessary for the production of` the colored object. Upon one of the light prints is then marked out on all necessary places the number of the color 1 on the scale corresponding with the original color. The percentage of each color found in the color-scale is now marked upon vthe remaining prints upon the proper places-*one print for each color. The prints thus obtained are now regulated with the brush, so that on the required 'places' the desired percentage of color isV represented in itsjequivalent in gray or black, a monochrome in gray and black for each color being thusuobtained.

Of these regulated prints, negativesof -exactly corresponding sizes are produced, and lightprinting plates of them prepared in the usual manner. The plate which has been obtained for the yellow color is now printedwith yellow color, the plate for the red'color is printed with red color, and the plate for the blue color is printed in blue color, the plates being made to register properly. These three colors combined give now a tolerably well-colored picture, which will be greatly improved and appear more finished by the use of the fourth plate,which is printed with the neutral tone.

For the productionof finer effects the use of the fifth plate, with which the local or flesh tint is printed, is in certain places often very desirable, Where esh or local tints enter into the composition. The use of the sixth plate is required when it is desired to heighten the effect of the red color, as madder-lake, owing to lack of body, often requires strengthening.

By means of the above-described process even persons of little artistic ability can succeed after a short time to produce very fine and faithful'eolored reproductions, which far surpass in softnessand strength of color all chromolithographic pictures, in which the colors necessarily lose much of their strength and purity by considerable additions of varnish; and while I obtain with four or five plates in my process practically a better re'- sult than is-'obtained in ehromographywith fifteen or twenty plates, the preparation of my plates does not require moretime than of-l be drawn directly with the brush and pencil.

My process for light printing in colors by the use of a color-scale can be applied with great advantage to the production of color- I OO ous when itis considered that Withthe thick pigments used in light printing :flatter and soiter tones `can be rproduced than with the much-diluted pigments necessary for iiat tones inlithography. Finely-ground ilux forms a necessary addition to the pigments to produce their burning in under the glaze, and generally three times the weight of the pigment is the amount of ilux required. The pigment and flux are then intimately mixed together with balsani of copaiba, to the proper consistency, which will allow,wheu desired, the powderingin process to be combinedwith the light-printing process. ed upon a temporary support on a thin film of copaibabalsam laidon with the roller,or on a y filmer" collodion.

To prepa-re my color-scale adapted to the productionoil pictures upon porcelain, l proceed as above described, except Where otherwise stated. The printingis doneupon a temporary support and with porcelain colors. The succession in which the pigments are printed depends upon their relative fusibility, and the printing is temporarilyinterrupted as soon as those pigments which easily fuse together and are mixed with the same flux are printed upon the temporary support, from which they are now transferred upon a porcelain plate and burned in. After this is done, the printing on a temporary support is thenl proceeded with, transposing the plate with each new color the Width of one square -to the right. This second color-scale, containing the .remaining colorssuch as purple and coburning in, the color-scale upon the porcelain plate is completed, and will show asa collection of different colors in as large a variety of shades and tints as the color-scale on The co1orprints are iirst mount-A into its composition.

For the poWdering-in process a color-scale constructed after the principle herein described Will be found of very great use for such process, as the colors can be thereby likewise mechanically dennoch By comparing the object to be reproduced with the color-scale upon porcelain it is now easy to tell how many and what colors are required, and also how often they have to be burned in, so that a fine oil-painting can be reproduced ,upon porcelain in all itsstrength and effects, together with its technical qualities. The color-scale upon porcelain gives to the artist an intimate knowledge of the relative iniluences of the pigments upon each other and of their behavior in the re--a knowledge which formerly required many years of practical experience; a-nd combined with my process of light printing in colors the technical difficulties of `painting upon porcelain have been entirely done away with by the photographic transferring.

I am aware of the Patent No. 17 3,408, and I do not claim a color-.sample card having directions for mixing the colors, as described in said patent.

What I claim as my invention is 1. The process herein set forth of producing color-printing plates bythe aid o1 a colorscale, consisting in first producing a number of nentralprintsfromagivenphoto-negative,next marking upon one of the neutral prints, on all necessary places, the number or symbol of the color or combinations of color on the scale corresponding with the original colo r, next representing upon the remaining neutral prints L the desired percentage of color in its equivalent shade in gray or black, and iinally using said prints to produce relief-printing plates, substantially as specified. A

Y 2. As a new article of manufacture, the colorscale herein described; provided on its surface with separateseries cfa number of colors in different tints, and a separate Series of different shades of aneutral tint, to correspondwith the tints of the colors, the depth of the shade and tint being designated by gures or other symbols, and the whole adapted to be used to indicate the shade of neutral tint corresponding with the desired tint of color upon the print or object desired, substantially as specified. F. CARL HOSGH. Witnesses:

OTTO ELTERIoH, PAUL REissMANN.

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